the new commander of coalition forces in afghanistan acknowledged the heavy price american and british troops paid for the progress made here. >> there are some voices that are raised to question whether this sacrifice has been worth it. those of us who wear this uniform have one answer -- yes! >> reporter: it was certainly a proud moment for the afghans as the defense minister inspected his troops. the handover of power from coalition to afghan forces has been done with pomp and ceremony. it is considered one of the most volatile places that will northbound afghan control. the real test will be if afghan forces can secure the city on their own without foreign troops jumping back in to help. aa top u.s. diplomat admitted too soon to count the taliban out. >> the gains that have been made are potentially reversible, but today is an important step forward for afghanistan. >> reporter: most of helmand will still be controlled by foreign forces. but the exit strategy was plain to see. even choreographed as british and u.s. troops marched off and the afghans rolled in. mandy clark, cbs news